My brother has just received a text asking him to go for the vaccine. Big northern city. He's 25 - 3 years younger than me. I live in a Southern suburb.
The only things we can think are he was investigated for MS-like symptoms a few years back (everything came back clear.) He also used to be very overweight, but he's now very slim (I probably weigh more than him now.) 
Are some places just that far ahead or is it likely to be another reason?